This application claims the priority of German application 196 46 956.2, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a process for repairing paint faults in paint layers, particularly paint faults of relatively small size in powder coating layers.
A process for the repair of paint faults is known from Japanese patent document JP 1-315 374 (A), from which it is known to remove relatively small paint faults, so-called hot-spots, by means of a drill. The remaining, largely cylindrical cutout is filled with a liquid repair paint, which is partly covered with a mask. The mask has a clearance in the region of the cutout filled with repair paint, through which clearance a laser light can be directed onto the repair paint. By means of the energy introduced by the laser light, the repair paint is heated and joined to the paint layer surrounding the cutout.
If it is attempted to transfer such a process to powder coating layers made of powder coating and/or powder slurry--referred to below simply as powder coating--the result is unsatisfactory, even with a substantial effort. In the case of so-called effect powder coating layers, which have to be applied using an electrostatic spraying process, a process of this type may be even wholly unsuitable, since then in the region of the cutout the effect of the powder coating layer is not visible and the previously faulty point can still easily be seen. For this reason, inter alia, faulty areas that are powder coated using effect paints are repainted over the entire area.
In the case of repainting using powder coating, in particular in the case of motor vehicles, virtually all parts sensitive to high temperatures and therefore virtually all plastic parts would have to be removed in a manner that costs effort and money, for which reason in this case the repair is generally performed using normal liquid paints. In the case of faulty painting in so-called space frames, which are provided with already colored built-on parts following their painting, although this does not apply to the same extent, nevertheless the effort for the repair is very high here too, and/or in the case of effect powder coatings likewise unsuitable for the reasons already cited.
Thus, there is a need for a process with which even powder coatings, in particular effect powder coatings, can be repaired relatively simply and inexpensively, and with a good visual quality.
These and other needs have been met according to the present invention by providing a process for repairing a paint fault in a powder coating layer, comprising the steps of: removing a portion of said powder coating layer in an area proximate and surrounding said fault to define a cutout having dimensions; forming a filler from at least one of said powder coating and a pre-product of said powder coating, said filler being formed to be at least partially coherent with dimensions corresponding to the dimensions of said cutout; introducing said filler into said cutout; and joining said filler to said powder coating layer defining said cutout.
These and other needs have also been met according to the present invention by providing a repaired powder coating layer formed by: removing a portion of a powder coating layer in an area proximate and surrounding a fault to define a cutout having dimensions; forming a filler from at least one of said powder coating and a pre-product of said powder coating, said filler being formed to be at least partially coherent with dimensions corresponding to the dimensions of said cutout; introducing said filler into said cutout; and joining said filler to said powder coating layer defining said cutout.
According to the present invention, the cutout is introduced with precisely defined dimensions with respect to its area and also with respect to its depth into the powder coating layer. Accordingly, it is subsequently possible to introduce into the cutout a filler made of powder coating and/or a pre-product of the powder coating, which is sized to correspond to the dimensions and volume of the cutout, in particular to provide a mating fit between the filler and the cutout. The filler is at least partially cross-linked prior to introduction into the cutout.
The filler introduced into the cutout is subsequently joined, in particular bonded or fully cross-linked, to the powder coating layer defining the cutout. The joining between the cutout and the filler takes place along at least a portion of the mating dimensions therebetween, and optionally along an entirety of the mating dimensions.
The repair according to the invention can be performed rapidly and relatively inexpensively. At the same time, the repair can also be performed on the production line, which is in particular beneficial in the case of vehicles having a self-supporting frame according to the space-frame concept. At the same time, by comparison with a repair over a large area using wet paint, the repair process has a low emission, due to the limited size of the repaired area as well as the use of an at least partially cross-linked filler, which results in a lower outlay on filters and cleaning, as well as a lower outlay on disposal and overspray. Hence, these advantages result in a reduced overall cost of the process.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.